Myotomes and Differentiating Nerve Lesions


  • Shoulder Abduction – C5 (axillary)
  • Shoulder Adduction – C678
  • Elbow Flexion – C5 (musculocutaneous)
  • Elbow Extension – C7 (radial)
  • Wrist Flexion & Extension – C67 (radial)
  • Finger Flexion – C8 (median)
  • Finger Extension – C7 (radial – posterior interosseous)
  • Finger Abduction – T1 (ulnar)
  • Abductor pollicis brevis – T1 (median)

Sorting out Muscles

  • biceps vs brachioradialis (both test C56: tests musculocutaneous nerve vs radial, note biceps jerk)
  • abductor pollicis brevis vs first dorsal interosseous (both T1: test median vs ulnar)
  • abductor pollicis brevis vs flexor pollicis longus (both median but abductor polis brevis supplied after the carpal tunnel)


  • Hip Flexion – L2 (femoral)
  • Hip Extension – L5 (inferior gluteal)
  • Knee Extension – L34 (femoral)
  • Knee Flexion – S1 (sciatic)
  • Ankle dorsiflexion – L4 (deep peroneal)
  • Ankle plantarflexion – S1 (tibial)
  • Great toe flexor – L5 (deep peroneal)

Sorting out Muscles

  • ankle dorsiflexors vs ankle inversion (both L4: tests deep peroneal vs tibial)
  • ankle dorsiflexors vs ankle evertors (both common peroneal nerve tests: tests superficial vs deep)
  • ankle dorsiflexors vs great toe flexor (both deep peroneal nerve tests L4 vs L5)

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

One comment

  1. Hi. The comment “ankle dorsiflexors vs ankle inversion (both L4: tests deep peroneal vs tibial)” is incorrect. Inversion is testing L5 via the tibial nerve, not L4.

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